S104 Abstracts / Brachytherapy 13 (2014) S15eS126

planning. Percent dose differences were less 3% for both ICRU bladder andrectal points, regardless of VC sizes. The use of closest rectal point is notrecommended for estimating rectal dose.

Figure 1B. Mean %-dose differences and other statistical analyses for

ICRU and closest rectum point using Dose-distance modeling.

Figure 1A. Dose-distance modeling for ICRU and closest rectal points on

four vaginal cylinder (VC) diameters.

PO39

Skin HDR Using the Varian Catheter Flap: A Case Study

Ileana Iftimia, PhD, Per Halvorsen, MS, Eileen Cirino, MS, Janna Finn,

CMD, Andrea McKee, MD. Radiation Oncology, Lahey Clinic, Burlington,

MA.

Purpose: To design an appropriate treatment approach for a patient whodeveloped skin cancer on the left face/scalp and neck areas and waspreviously treated with external beam radiotherapy (EBRT) and HDR tothe right neck and face/scalp regions, respectively.Materials and Methods: The patient was treated in 2012 to the right faceand scalp using an HDR flap technique, with a total dose of 51 Gy in 17fractions at 3 mm depth. He was also treated a few years earlier for aright neck tumor using an EBRT technique. The new left face and scalpHDR field was designed to avoid overlap with the concomitant left neckEBRT fields and with the prior HDR field to the right face and scalp. Twosimulation sessions were scheduled for this case. During the first session,a mask was created and the left neck EBRT field borders weredetermined. The previous right face/scalp mask with HDR flap had beenpreserved to facilitate reconstruction of the treated volume in the event ofre-treatment. A PTV for the left face/scalp HDR plan was contoured onthe mask guided inferiorly by the left neck EBRT light field edge andsuperiorly by the PTV for the previous HDR right face/scalp plan. A wirewas placed over the PTV contour. The required shape, size andorientation of the flap were evaluated. Needles were subsequently placed1 cm apart inside the flap channels. The flap was carefully sutured overthe mask with multiple stitches, to ensure no air gap between the flap andthe mask, especially over the PTV region. During the second simulationsession, CT images were acquired with the mask/flap in place and dummywires inserted in each channel. A radiopaque marker was placed nearneedle #1 to help identify the needle numbers. The needles andcorresponding source guide tubes were then labeled. The images wereexported to Brachyvision, where needles were identified and the wire wascontoured. The PTV was defined with a thickness of 3 mm, and limited inthe other two dimensions by the wire. Critical structures (left eye-lens andskin) were contoured. The prescription was 51 Gy at 3 mm depth in 17fractions, with 2 fractions per week. A plan was performed using avolume optimization approach. The following criteria were used: PTVD90%O 100%Rx; skin D 0.04cc! 145%Rx. The plan was exported tothe HDR unit and a dry test was performed without the patient present toensure that the needles had no obstruction and that their curvature wasacceptable for treatment delivery. All HDR and EBRT plans wereexported to MIM and a composite plan was obtained. The skin dose at thefield interfaces and the left eye/lens dose were assessed.Results: Using this methodology a clinically reasonable HDR plan wasdeveloped, meeting all criteria: PTV D90% was 103.6%Rx; skin D0.04cc was 141%Rx; skin D 1cc was 130%Rx. The independent dosecalculation agreement was within 1.5%. The PTVs for the right and leftHDR plans abutted in a single slice. In all other slices there was a gap inbetween the two PTV structures. The composite isodose distribution wasalso analyzed, showing a small overlap area on the top of the head. Noother overlap was observed. The DVH for the left eye/lens and for theskin at the interfaces was obtained and analyzed in MIM. The maximumskin dose from all plans was 125 Gy. The maximum calculated dose tothe left eye was 50 Gy. The elapsed time between various treatmentprocedures was not taken into account for this composite plan, so theeffective dose to the critical structures may be lower. The patient is blindin the right eye. To reduce the left lens dose, an eye shield was placedover the mask for the HDR treatments and the patient was asked to lookto his right side. Measurements using OSL dosimeters were alsoperformed for the left eye dose during the first treatment. The dose to theshielded left eye was reduced to 10 Gy for the HDR treatments.Conclusions: The patient finished the HDR and EBRT treatments for theleft face/scalp and neck areas without major difficulties. The skinappearance improved. Followup will be needed to demonstrate theefficacy of the treatment.

PO40

A Comparison of Forward Planning vs. Inverse Planning Simulated

Annealing for Accelerated Partial Breast Irradiation Multi Channel

Catheter Brachytherapy

Meredith A. Semon, MS, Mohsen Isaac, MD, Michael Semon, MS.

Radiation Oncology, Monongahela Valley Hospital, Monongahela, PA.

S105Abstracts / Brachytherapy 13 (2014) S15eS126

Purpose: Provide a comparison and educate those planning AcceleratedPartial Breast Irradiation (APBI) multi channel catheter brachytherapywith either forward or inverse planning systems for a skin distance ofless than 7mm. The following will demonstrate, in this particularstudy, which of the two planning processes is more beneficial for thepatient.Materials and Methods: Prior to this study, the participating clinic usedInverse Planning Simulated Annealing (IPSA) for all of its APBI multichannel catheter brachytherapy planning purposes. In order to make acomparison of the forward planning and the IPSA results, a selection of3 out of 56 patients were chosen that had a skin distance of less than7mm. These three patients A,B, and C then received a planning CT andwere contoured identically. Firstly for all 3 of the patients the forwardplan was completed. The next step was to place the catheters in the 4channels and then activate all of the possible dwell positions. Duringthe forward planning process, points were then dropped on the outeredge of the PTVeval in order to normalize and optimize the prescriptiondose of 340cGy to these selected points. Then using the NSABP 39protocol, a set of predetermined information is compared to theoutcome of the current plan and can then be changed in order to fallwithin the guidelines. The plan was then adjusted by different methodsincluding graphical manipulation and changing or eliminating themanual weighting of the dwells. This process was completed until theplanner and doctor were satisfied with the outcomes of the statedcriteria. In regards to IPSA based planning, first the catheters arereconstructed but then the input IPSA presets are used and a plan iscreated. This plan was then adjusted by simply changing the dose andweight to various targets and OAR’s. This process was again completeduntil the criteria were met.Results: Patients A, B, and C were then evaluated and compared forcertain previously determined criteria. Table 1 shows the planningstructure evaluation for all of the patients. As it is shown for 2/3patients, the V150 and maximum rib dose were lower for the forwardplaning process. For all 3 of the patients, the V200 and whole breastevaluations were also lower for the forward planning process. On theother hand, 2/3 patients had a lower maximum skin dose with IPSA.Finally the V90 and the time to plan were almost equivalent for boththe forward and IPSA planning process. From these results, it can beconcluded that forward planning could be as good as or even better incertain circumstances than IPSA.Conclusions: Despite this study only containing 3 patients, it still providesinsight into using the more appropriate planning process to benefit thepatient. This study shows that forward planning is as good or even betterthan using IPSA for treatment planning of APBI multi catheterbrachytherapy in a selected class of patients. Therefore, for an initialstart-up clinic using the IPSA based planning would be easier. Then onceexperience has been gained by the planner, using forward planning couldbe accomplished. In order to continue this study, all of the patients at thisparticular institution will be planned with both forward and IPSAplanning processes and a comparison will be made in order to choose thebest plan for each patient.

Table 1

Planning Structure Evaluation

PATIENT A

MANUAL IPSA

V150 OF PTV_EVAL (cc) 19.03 22.14

V200 OF PTV_ EVAL (cc) 4.84 7.37

V90 OF PTV_EVAL 91.56% 91.88%

WHOLE BREAST EVAL 43.42% 44.90%

MAX RIB DOSE (cGy) 481 456

MAX SKIN DOSE (cGy) 443 462

TIME TO PLAN 20:28.00 14:14.00

PO41

Technological Solutions for the Transition to an Electronic Medical

Record System in a High-Dose-Rate Brachytherapy Practice

Antonio L. Damato, PhD, Robert A. Cormack, PhD, Desmond A.

O’Farrell, MS, Scott A. Friesen, MS, Mandar S. Bhagwat, PhD, Ivan

Buzurovic, PhD, Adi Heller, BA, Megan Carroll, BA, Larissa J. Lee, MD,

Akila N. Viswanathan, MD, Phillip M. Devlin, MD, Jorgen L. Hansen, MS.

Radiation Oncology, Dana-Farber Cancer Institute /Brigham and

Women’s Hospital, Boston, MA.

Purpose: To describe solutions for the transition of a high-dose-rate (HDR)brachytherapy practice from a chart-based medical record environment to achartless electronic medical record (EMR) environment.Materials and Methods: Our department transitioned to EMR in January2013. The ARIA (VarianMedical Systems, Inc., Palo Alto, CA) record-and-verify system was available and in use in the department for external-beamtreatments. All HDR treatments were planned with Oncentra Brachy(Nucletron, an Elekta company, Stockholm, Sweden) and delivered usingtwo Nucletron V3 afterloaders with two independent treatment consoleunits. Before the transition, the written directive, plan records (planprintout, physics checks, clinical photos and treatment worksheet) andtreatment records were signed on paper and stored in the patient’s chart.Peer review of the treatments, consisting of a review of the chartdocumentation in the presence of at least two attending physicians andrepresentatives of physics and therapy, was done bi-weekly.Results: After the transition to EMR, record-and-verify information washandled in ARIA. Dose points representing the prescription point, planTRAK value, and OAR metrics were associated with an ARIA plan. Eachtreatment fraction is manually completed in ARIA by the treating physicist.The paper written directive was replaced by a dynamic document in ARIA,the electronic written directive (eWD) (see Figure). Authorized user’ssignature of the eWD is acquired by the secure document approval systemin ARIA before planning and again, through electronic amendment, beforeevery fraction. All amendments of the eWD are available for audit.Treatment plan information and physics check information are directlyprinted from the planning system and from an in-house automatedsecondary check software (BrachyVerifier) to portable document format(PDF) files which are merged into a single plan PDF file. The treatment planPDF file is signed by the planner and the second check physicist throughcertificate-based secure signature capabilities of Acrobat XI Pro (AdobeSystems Inc., San Jose, CA). The plan PDF file is imported into ARIA andis approved by the authorized user before the first fraction. The bi-weeklypeer review is conducted using in-house software (ChartViewer) displayingthe eWD, treatment plan information and treatment information from therecord-and-verify system. Although the transition to EMR was completed,some information is still stored and processed on paper, and scanned at theend of the treatment for storage in ARIA. A copy of the paper worksheet isstill in use for backup purposes, and day-of-treatment information is printedand signed by the authorized user and the authorized physicist by hand.Additional solutions for the implementation of a full transition to electronicformat are under testing.

PATIENT B PATIENT C

MANUAL IPSA MANUAL IPSA

19.09 24.53 19.07 18.29

4.45 8.31 3.89 4.02

90.45% 92.75% 91.19% 91.52

19.70% 20.96% 35.71% 35.82

351 393 368 391

480 454 453 386

13:15.00 14:26.00 12:05.00 10:33.00

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